update_chapter · BookStack MCP Server MCP: Risk & Policy

WHAT IT DOES

What update_chapter does on BookStack MCP Server

AI agents use update_chapter to create or update resources in BookStack MCP Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your BookStack MCP Server environment.

WHY IT NEEDS A POLICY

Why update_chapter needs a policy

The tool modifies an existing chapter in a wiki instance, which is a reversible Write operation. It does not execute arbitrary code (Execute), permanently delete data (Destructive), or move funds (Financial). Medium severity reflects that unauthorized chapter updates could corrupt wiki content or spread misinformation, but the action is reversible and limited in blast radius compared to destructive operations.

From the tool's definition Tool name is 'update_chapter' with description 'Update an existing chapter'. The verb 'update' indicates modification of existing data in a reversible manner, consistent with Write operations.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update_chapter Rate-limited

update_chapter stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "update_chapter": {
      "limits": [
        {
          "counter": "update_chapter_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches BookStack MCP Server, so you can run agents against it safely.

FAQ

Questions about update_chapter

What does the update_chapter tool do? +

Update an existing chapter. It is categorised as a Write tool in the BookStack MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on update_chapter? +

Register the BookStack MCP Server MCP server in PolicyLayer and add a rule for update_chapter: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches BookStack MCP Server. Nothing to install.

What risk level is update_chapter? +

update_chapter is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit update_chapter? +

Yes. Add a rate_limit block to the update_chapter rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block update_chapter completely? +

Set action: deny in the PolicyLayer policy for update_chapter. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides update_chapter? +

update_chapter is provided by the BookStack MCP Server MCP server (lautarobarba/bookstack_mcp_server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.